After four successful missions to the International Space Station, including three official resupply missions for NASA, SpaceX is set to launch its fourth official Commercial Resupply (CRS) mission to the orbiting lab. The SpaceX CRS-4 mission is targeting launch at 06:14 UTC Saturday, September 20 from Launch Complex 40 at the Cape Canaveral Air Force Station, Florida. If all goes as planned, Dragon will arrive at the station on Monday, September 22 for an expected four-week visit. Dragon is scheduled to return to Earth in mid-October for a parachute-assisted splashdown off the coast of southern California. Dragon is the only operational spacecraft capable of returning a significant amount of supplies back to Earth, including experiments.